/*
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package cn.ac.iie.ulss.datadispatch.util;

/**
 *
 * @author alexmu
 */
import java.util.Arrays;

/**
 *
 * A very fast and memory efficient class to encode and decode to and from
 *
 * BASE64 in full accordance with RFC 2045.<br>
 *
 * <br>
 *
 * On Windows XP sp1 with 1.4.2_04 and later ;), this encoder and decoder is
 *
 * about 10 times faster on small arrays (10 - 1000 bytes) and 2-3 times as fast
 *
 * on larger arrays (10000 - 1000000 bytes) compared to
 *
 * <code>sun.misc.Encoder()/Decoder()</code>.<br>
 *
 * <br>
 *
 *
 *
 * On byte arrays the encoder is about 20% faster than Jakarta Commons Base64
 *
 * Codec for encode and about 50% faster for decoding large arrays. This
 *
 * implementation is about twice as fast on very small arrays (< 30 bytes). If
 *
 * source/destination is a <code>String</code> this version is about three
 *
 * times as fast due to the fact that the Commons Codec result has to be recoded
 *
 * to a
 * <code>String</code> from
 * <code>byte[]</code>, which is very
 *
 * expensive.<br>
 *
 * <br>
 *
 *
 *
 * This encode/decode algorithm doesn't create any temporary arrays as many
 *
 * other codecs do, it only allocates the resulting array. This produces less
 *
 * garbage and it is possible to handle arrays twice as large as algorithms that
 *
 * create a temporary array. (E.g. Jakarta Commons Codec). It is unknown whether
 *
 * Sun's
 * <code>sun.misc.Encoder()/Decoder()</code> produce temporary arrays
 *
 * but since performance is quite low it probably does.<br>
 *
 * <br>
 *
 *
 *
 * The encoder produces the same output as the Sun one except that the Sun's
 *
 * encoder appends a trailing line separator if the last character isn't a pad.
 *
 * Unclear why but it only adds to the length and is probably a side effect.
 *
 * Both are in conformance with RFC 2045 though.<br>
 *
 * Commons codec seem to always att a trailing line separator.<br>
 *
 * <br>
 *
 *
 *
 * <b>Note!</b> The encode/decode method pairs (types) come in three versions
 *
 * with the <b>exact</b> same algorithm and thus a lot of code redundancy. This
 *
 * is to not create any temporary arrays for transcoding to/from different
 *
 * format types. The methods not used can simply be commented out.<br>
 *
 * <br>
 *
 *
 *
 * There is also a "fast" version of all decode methods that works the same way
 *
 * as the normal ones, but har a few demands on the decoded input. Normally
 *
 * though, these fast verions should be used if the source if the input is known
 *
 * and it hasn't bee tampered with.<br>
 *
 * <br>
 *
 *
 *
 * If you find the code useful or you find a bug, please send me a note at
 *
 * base64
 *
 * @ miginfocom . com.
 *
 *
 *
 * Licence (BSD): ==============
 *
 *
 *
 * Copyright (c) 2004, Mikael Grev, MiG InfoCom AB. (base64
 * @ miginfocom . com)
 *
 * All rights reserved.
 *
 *
 *
 * Redistribution and use in source and binary forms, with or without
 *
 * modification, are permitted provided that the following conditions are met:
 *
 * Redistributions of source code must retain the above copyright notice, this
 *
 * list of conditions and the following disclaimer. Redistributions in binary
 *
 * form must reproduce the above copyright notice, this list of conditions and
 *
 * the following disclaimer in the documentation and/or other materials provided
 *
 * with the distribution. Neither the name of the MiG InfoCom AB nor the names
 *
 * of its contributors may be used to endorse or promote products derived from
 *
 * this software without specific prior written permission.
 *
 *
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 *
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 *
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 *
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
 *
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 *
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 *
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 *
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 *
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 *
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 *
 * POSSIBILITY OF SUCH DAMAGE.
 *
 *
 *
 * @version 2.2
 *
 * @author Mikael Grev Date: 2004-aug-02 Time: 11:31:11
 *
 */
public class Base64 {

    private static final boolean devLineSep = true;
    private static final char[] CA = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"
            .toCharArray();
    private static final int[] IA = new int[256];

    static {

        Arrays.fill(IA, -1);

        for (int i = 0, iS = CA.length; i < iS; i++) {
            IA[CA[i]] = i;
        }

        IA['='] = 0;

    }

    // ****************************************************************************************
    // * char[] version
    // ****************************************************************************************
    public final static char[] encodeToChar(byte[] sArr) {

        return encodeToChar(sArr, devLineSep);

    }

    /**
     *
     * Encodes a raw byte array into a BASE64
     * <code>char[]</code>
     *
     * representation i accordance with RFC 2045.
     *
     *
     *
     * @param sArr
     *
     * The bytes to convert. If <code>null</code> or length 0 an
     *
     * empty array will be returned.
     *
     * @param lineSep
     *
     * Optional "\r\n" after 76 characters, unless end of file.<br>
     *
     * No line separator will be in breach of RFC 2045 which
     *
     * specifies max 76 per line but will be a little faster.
     *
     * @return A BASE64 encoded array. Never <code>null</code>.
     *
     */
    public final static char[] encodeToChar(byte[] sArr, boolean lineSep) {

        // Check special case

        int sLen = sArr != null ? sArr.length : 0;

        if (sLen == 0) {
            return new char[0];
        }



        int eLen = (sLen / 3) * 3; // Length of even 24-bits.

        int cCnt = ((sLen - 1) / 3 + 1) << 2; // Returned character count

        int dLen = cCnt + (lineSep ? (cCnt - 1) / 76 << 1 : 0); // Length of

        // returned

        // array

        char[] dArr = new char[dLen];



        // Encode even 24-bits

        for (int s = 0, d = 0, cc = 0; s < eLen;) {

            // Copy next three bytes into lower 24 bits of int, paying attension

            // to sign.

            int i = (sArr[s++] & 0xff) << 16 | (sArr[s++] & 0xff) << 8
                    | (sArr[s++] & 0xff);



            // Encode the int into four chars

            dArr[d++] = CA[(i >>> 18) & 0x3f];

            dArr[d++] = CA[(i >>> 12) & 0x3f];

            dArr[d++] = CA[(i >>> 6) & 0x3f];

            dArr[d++] = CA[i & 0x3f];



            // Add optional line separator

            if (lineSep && ++cc == 19 && d < dLen - 2) {

                dArr[d++] = '\r';

                dArr[d++] = '\n';

                cc = 0;

            }

        }



        // Pad and encode last bits if source isn't even 24 bits.

        int left = sLen - eLen; // 0 - 2.

        if (left > 0) {

            // Prepare the int

            int i = ((sArr[eLen] & 0xff) << 10)
                    | (left == 2 ? ((sArr[sLen - 1] & 0xff) << 2) : 0);



            // Set last four chars

            dArr[dLen - 4] = CA[i >> 12];

            dArr[dLen - 3] = CA[(i >>> 6) & 0x3f];

            dArr[dLen - 2] = left == 2 ? CA[i & 0x3f] : '=';

            dArr[dLen - 1] = '=';

        }

        return dArr;

    }

    /**
     *
     * Decodes a BASE64 encoded char array. All illegal characters will be
     *
     * ignored and can handle both arrays with and without line separators.
     *
     *
     *
     * @param sArr
     *
     * The source array. <code>null</code> or length 0 will return
     *
     * an empty array.
     *
     * @return The decoded array of bytes. May be of length 0. Will be
     *
     * <code>null</code> if the legal characters (including '=') isn't
     *
     * divideable by 4. (I.e. definitely corrupted).
     *
     */
    public final static byte[] decode(char[] sArr) {

        // Check special case

        int sLen = sArr != null ? sArr.length : 0;

        if (sLen == 0) {
            return new byte[0];
        }



        // Count illegal characters (including '\r', '\n') to know what size the

        // returned array will be,

        // so we don't have to reallocate & copy it later.

        int sepCnt = 0; // Number of separator characters. (Actually illegal

        // characters, but that's a bonus...)

        for (int i = 0; i < sLen; i++) // If input is "pure" (I.e. no line separators or illegal chars)
        // base64 this loop can be commented out.
        {
            if (IA[sArr[i]] < 0) {
                sepCnt++;
            }
        }



        // Check so that legal chars (including '=') are evenly divideable by 4

        // as specified in RFC 2045.

        if ((sLen - sepCnt) % 4 != 0) {
            return null;
        }



        int pad = 0;

        for (int i = sLen; i > 1 && IA[sArr[--i]] <= 0;) {
            if (sArr[i] == '=') {
                pad++;
            }
        }



        int len = ((sLen - sepCnt) * 6 >> 3) - pad;



        byte[] dArr = new byte[len]; // Preallocate byte[] of exact length



        for (int s = 0, d = 0; d < len;) {

            // Assemble three bytes into an int from four "valid" characters.

            int i = 0;

            for (int j = 0; j < 4; j++) { // j only increased if a valid char

                // was found.

                int c = IA[sArr[s++]];

                if (c >= 0) {
                    i |= c << (18 - j * 6);
                } else {
                    j--;
                }

            }

            // Add the bytes

            dArr[d++] = (byte) (i >> 16);

            if (d < len) {

                dArr[d++] = (byte) (i >> 8);

                if (d < len) {
                    dArr[d++] = (byte) i;
                }

            }

        }

        return dArr;

    }

    /**
     *
     * Decodes a BASE64 encoded char array that is known to be resonably well
     *
     * formatted. The method is about twice as fast as {@link #decode(char[])}.
     *
     * The preconditions are:<br> + The array must have a line length of 76
     *
     * chars OR no line separators at all (one line).<br> + Line separator must
     *
     * be "\r\n", as specified in RFC 2045 + The array must not contain illegal
     *
     * characters within the encoded string<br> + The array CAN have illegal
     *
     * characters at the beginning and end, those will be dealt with
     *
     * appropriately.<br>
     *
     *
     *
     * @param sArr
     *
     * The source array. Length 0 will return an empty array.
     *
     * <code>null</code> will throw an exception.
     *
     * @return The decoded array of bytes. May be of length 0.
     *
     */
    public final static byte[] decodeFast(char[] sArr) {

        // Check special case

        int sLen = sArr.length;

        if (sLen == 0) {
            return new byte[0];
        }



        int sIx = 0, eIx = sLen - 1; // Start and end index after trimming.



        // Trim illegal chars from start

        while (sIx < eIx && IA[sArr[sIx]] < 0) {
            sIx++;
        }



        // Trim illegal chars from end

        while (eIx > 0 && IA[sArr[eIx]] < 0) {
            eIx--;
        }



        // get the padding count (=) (0, 1 or 2)

        int pad = sArr[eIx] == '=' ? (sArr[eIx - 1] == '=' ? 2 : 1) : 0; // Count

        // '='

        // at

        // end.

        int cCnt = eIx - sIx + 1; // Content count including possible

        // separators

        int sepCnt = sLen > 76 ? (sArr[76]
                == '\r'
                ? cCnt / 78 : 0) << 1 : 0;



        int len = ((cCnt - sepCnt) * 6 >> 3) - pad; // The number of decoded

        // bytes

        byte[] dArr = new byte[len]; // Preallocate byte[] of exact length



        // Decode all but the last 0 - 2 bytes.

        int d = 0;

        for (int cc = 0, eLen = (len / 3) * 3; d < eLen;) {

            // Assemble three bytes into an int from four "valid" characters.

            int i = IA[sArr[sIx++]] << 18 | IA[sArr[sIx++]] << 12
                    | IA[sArr[sIx++]] << 6 | IA[sArr[sIx++]];



            // Add the bytes

            dArr[d++] = (byte) (i >> 16);

            dArr[d++] = (byte) (i >> 8);

            dArr[d++] = (byte) i;



            // If line separator, jump over it.

            if (sepCnt > 0 && ++cc == 19) {

                sIx += 2;

                cc = 0;

            }

        }



        if (d < len) {

            // Decode last 1-3 bytes (incl '=') into 1-3 bytes

            int i = 0;

            for (int j = 0; sIx <= eIx - pad; j++) {
                i |= IA[sArr[sIx++]] << (18 - j * 6);
            }



            for (int r = 16; d < len; r -= 8) {
                dArr[d++] = (byte) (i >> r);
            }

        }



        return dArr;

    }

    // ****************************************************************************************
    // * byte[] version
    // ****************************************************************************************
    public final static byte[] encodeToByte(byte[] sArr) {

        return encodeToByte(sArr, devLineSep);

    }

    /**
     *
     * Encodes a raw byte array into a BASE64
     * <code>byte[]</code>
     *
     * representation i accordance with RFC 2045.
     *
     *
     *
     * @param sArr
     *
     * The bytes to convert. If <code>null</code> or length 0 an
     *
     * empty array will be returned.
     *
     * @param lineSep
     *
     * Optional "\r\n" after 76 characters, unless end of file.<br>
     *
     * No line separator will be in breach of RFC 2045 which
     *
     * specifies max 76 per line but will be a little faster.
     *
     * @return A BASE64 encoded array. Never <code>null</code>.
     *
     */
    public final static byte[] encodeToByte(byte[] sArr, boolean lineSep) {

        // Check special case

        int sLen = sArr != null ? sArr.length : 0;

        if (sLen == 0) {
            return new byte[0];
        }



        int eLen = (sLen / 3) * 3; // Length of even 24-bits.

        int cCnt = ((sLen - 1) / 3 + 1) << 2; // Returned character count

        int dLen = cCnt + (lineSep ? (cCnt - 1) / 76 << 1 : 0); // Length of

        // returned

        // array

        byte[] dArr = new byte[dLen];



        // Encode even 24-bits

        for (int s = 0, d = 0, cc = 0; s < eLen;) {

            // Copy next three bytes into lower 24 bits of int, paying attension

            // to sign.

            int i = (sArr[s++] & 0xff) << 16 | (sArr[s++] & 0xff) << 8
                    | (sArr[s++] & 0xff);



            // Encode the int into four chars

            dArr[d++] = (byte) CA[(i >>> 18) & 0x3f];

            dArr[d++] = (byte) CA[(i >>> 12) & 0x3f];

            dArr[d++] = (byte) CA[(i >>> 6) & 0x3f];

            dArr[d++] = (byte) CA[i & 0x3f];



            // Add optional line separator

            if (lineSep && ++cc == 19 && d < dLen - 2) {

                dArr[d++] = '\r';

                dArr[d++] = '\n';

                cc = 0;

            }

        }



        // Pad and encode last bits if source isn't an even 24 bits.

        int left = sLen - eLen; // 0 - 2.

        if (left > 0) {

            // Prepare the int

            int i = ((sArr[eLen] & 0xff) << 10)
                    | (left == 2 ? ((sArr[sLen - 1] & 0xff) << 2) : 0);



            // Set last four chars

            dArr[dLen - 4] = (byte) CA[i >> 12];

            dArr[dLen - 3] = (byte) CA[(i >>> 6) & 0x3f];

            dArr[dLen - 2] = left == 2 ? (byte) CA[i & 0x3f] : (byte) '=';

            dArr[dLen - 1] = '=';

        }

        return dArr;

    }

    /**
     *
     * Decodes a BASE64 encoded byte array. All illegal characters will be
     *
     * ignored and can handle both arrays with and without line separators.
     *
     *
     *
     * @param sArr
     *
     * The source array. Length 0 will return an empty array.
     *
     * <code>null</code> will throw an exception.
     *
     * @return The decoded array of bytes. May be of length 0. Will be
     *
     * <code>null</code> if the legal characters (including '=') isn't
     *
     * divideable by 4. (I.e. definitely corrupted).
     *
     */
    public final static byte[] decode(byte[] sArr) {

        // Check special case

        int sLen = sArr.length;



        // Count illegal characters (including '\r', '\n') to know what size the

        // returned array will be,

        // so we don't have to reallocate & copy it later.

        int sepCnt = 0; // Number of separator characters. (Actually illegal

        // characters, but that's a bonus...)

        for (int i = 0; i < sLen; i++) // If input is "pure" (I.e. no line separators or illegal chars)
        // base64 this loop can be commented out.
        {
            if (IA[sArr[i] & 0xff] < 0) {
                sepCnt++;
            }
        }



        // Check so that legal chars (including '=') are evenly divideable by 4

        // as specified in RFC 2045.

        if ((sLen - sepCnt) % 4 != 0) {
            return null;
        }



        int pad = 0;

        for (int i = sLen; i > 1 && IA[sArr[--i] & 0xff] <= 0;) {
            if (sArr[i] == '=') {
                pad++;
            }
        }



        int len = ((sLen - sepCnt) * 6 >> 3) - pad;



        byte[] dArr = new byte[len]; // Preallocate byte[] of exact length



        for (int s = 0, d = 0; d < len;) {

            // Assemble three bytes into an int from four "valid" characters.

            int i = 0;

            for (int j = 0; j < 4; j++) { // j only increased if a valid char

                // was found.

                int c = IA[sArr[s++] & 0xff];

                if (c >= 0) {
                    i |= c << (18 - j * 6);
                } else {
                    j--;
                }

            }



            // Add the bytes

            dArr[d++] = (byte) (i >> 16);

            if (d < len) {

                dArr[d++] = (byte) (i >> 8);

                if (d < len) {
                    dArr[d++] = (byte) i;
                }

            }

        }



        return dArr;

    }

    /**
     *
     * Decodes a BASE64 encoded byte array that is known to be resonably well
     *
     * formatted. The method is about twice as fast as {@link #decode(byte[])}.
     *
     * The preconditions are:<br> + The array must have a line length of 76
     *
     * chars OR no line separators at all (one line).<br> + Line separator must
     *
     * be "\r\n", as specified in RFC 2045 + The array must not contain illegal
     *
     * characters within the encoded string<br> + The array CAN have illegal
     *
     * characters at the beginning and end, those will be dealt with
     *
     * appropriately.<br>
     *
     *
     *
     * @param sArr
     *
     * The source array. Length 0 will return an empty array.
     *
     * <code>null</code> will throw an exception.
     *
     * @return The decoded array of bytes. May be of length 0.
     *
     */
    public final static byte[] decodeFast(byte[] sArr) {

        // Check special case

        int sLen = sArr.length;

        if (sLen == 0) {
            return new byte[0];
        }



        int sIx = 0, eIx = sLen - 1; // Start and end index after trimming.



        // Trim illegal chars from start

        while (sIx < eIx && IA[sArr[sIx] & 0xff] < 0) {
            sIx++;
        }



        // Trim illegal chars from end

        while (eIx > 0 && IA[sArr[eIx] & 0xff] < 0) {
            eIx--;
        }



        // get the padding count (=) (0, 1 or 2)

        int pad = sArr[eIx] == '=' ? (sArr[eIx - 1] == '=' ? 2 : 1) : 0; // Count

        // '='

        // at

        // end.

        int cCnt = eIx - sIx + 1; // Content count including possible

        // separators

        int sepCnt = sLen > 76 ? (sArr[76]
                == '\r'
                ? cCnt / 78 : 0) << 1 : 0;



        int len = ((cCnt - sepCnt) * 6 >> 3) - pad; // The number of decoded

        // bytes

        byte[] dArr = new byte[len]; // Preallocate byte[] of exact length



        // Decode all but the last 0 - 2 bytes.

        int d = 0;

        for (int cc = 0, eLen = (len / 3) * 3; d < eLen;) {

            // Assemble three bytes into an int from four "valid" characters.

            int i = IA[sArr[sIx++]] << 18 | IA[sArr[sIx++]] << 12
                    | IA[sArr[sIx++]] << 6 | IA[sArr[sIx++]];



            // Add the bytes

            dArr[d++] = (byte) (i >> 16);

            dArr[d++] = (byte) (i >> 8);

            dArr[d++] = (byte) i;



            // If line separator, jump over it.

            if (sepCnt > 0 && ++cc == 19) {

                sIx += 2;

                cc = 0;

            }

        }



        if (d < len) {

            // Decode last 1-3 bytes (incl '=') into 1-3 bytes

            int i = 0;

            for (int j = 0; sIx <= eIx - pad; j++) {
                i |= IA[sArr[sIx++]] << (18 - j * 6);
            }



            for (int r = 16; d < len; r -= 8) {
                dArr[d++] = (byte) (i >> r);
            }

        }



        return dArr;

    }

    // ****************************************************************************************
    // * String version
    // ****************************************************************************************
    /**
     *
     * Encodes a raw byte array into a BASE64
     * <code>String</code>
     *
     * representation i accordance with RFC 2045.
     *
     *
     *
     * @param sArr
     *
     * The bytes to convert. If <code>null</code> or length 0 an
     *
     * empty array will be returned.
     *
     * @param lineSep
     *
     * Optional "\r\n" after 76 characters, unless end of file.<br>
     *
     * No line separator will be in breach of RFC 2045 which
     *
     * specifies max 76 per line but will be a little faster.
     *
     * @return A BASE64 encoded array. Never <code>null</code>.
     *
     */
    public final static String encodeToString(byte[] sArr, boolean lineSep) {

        // Reuse char[] since we can't create a String incrementally anyway and

        // StringBuffer/Builder would be slower.

        return new String(encodeToChar(sArr, lineSep));

    }

    public final static String encodeToString(byte[] sArr) {

        // Reuse char[] since we can't create a String incrementally anyway and

        // StringBuffer/Builder would be slower.

        return new String(encodeToChar(sArr, devLineSep));

    }

    /**
     *
     * Decodes a BASE64 encoded
     * <code>String</code>. All illegal characters
     *
     * will be ignored and can handle both strings with and without line
     *
     * separators.<br>
     *
     * <b>Note!</b> It can be up to about 2x the speed to call
     *
     * <code>decode(str.toCharArray())</code> instead. That will create a
     *
     * temporary array though. This version will use
     * <code>str.charAt(i)</code>
     *
     * to iterate the string.
     *
     *
     *
     * @param str
     *
     * The source string. <code>null</code> or length 0 will return
     *
     * an empty array.
     *
     * @return The decoded array of bytes. May be of length 0. Will be
     *
     * <code>null</code> if the legal characters (including '=') isn't
     *
     * divideable by 4. (I.e. definitely corrupted).
     *
     */
    public final static byte[] decode(String str) {

        // Check special case

        int sLen = str != null ? str.length() : 0;

        if (sLen == 0) {
            return new byte[0];
        }



        // Count illegal characters (including '\r', '\n') to know what size the

        // returned array will be,

        // so we don't have to reallocate & copy it later.

        int sepCnt = 0; // Number of separator characters. (Actually illegal

        // characters, but that's a bonus...)

        for (int i = 0; i < sLen; i++) // If input is "pure" (I.e. no line separators or illegal chars)
        // base64 this loop can be commented out.
        {
            if (IA[str.charAt(i)] < 0) {
                sepCnt++;
            }
        }



        // Check so that legal chars (including '=') are evenly divideable by 4

        // as specified in RFC 2045.

        if ((sLen - sepCnt) % 4 != 0) {
            return null;
        }



        // Count '=' at end

        int pad = 0;

        for (int i = sLen; i > 1 && IA[str.charAt(--i)] <= 0;) {
            if (str.charAt(i) == '=') {
                pad++;
            }
        }



        int len = ((sLen - sepCnt) * 6 >> 3) - pad;



        byte[] dArr = new byte[len]; // Preallocate byte[] of exact length



        for (int s = 0, d = 0; d < len;) {

            // Assemble three bytes into an int from four "valid" characters.

            int i = 0;

            for (int j = 0; j < 4; j++) { // j only increased if a valid char

                // was found.

                int c = IA[str.charAt(s++)];

                if (c >= 0) {
                    i |= c << (18 - j * 6);
                } else {
                    j--;
                }

            }

            // Add the bytes

            dArr[d++] = (byte) (i >> 16);

            if (d < len) {

                dArr[d++] = (byte) (i >> 8);

                if (d < len) {
                    dArr[d++] = (byte) i;
                }

            }

        }

        return dArr;

    }

    /**
     *
     * Decodes a BASE64 encoded string that is known to be resonably well
     *
     * formatted. The method is about twice as fast as {@link #decode(String)}.
     *
     * The preconditions are:<br> + The array must have a line length of 76
     *
     * chars OR no line separators at all (one line).<br> + Line separator must
     *
     * be "\r\n", as specified in RFC 2045 + The array must not contain illegal
     *
     * characters within the encoded string<br> + The array CAN have illegal
     *
     * characters at the beginning and end, those will be dealt with
     *
     * appropriately.<br>
     *
     *
     *
     * @param s
     *
     * The source string. Length 0 will return an empty array.
     *
     * <code>null</code> will throw an exception.
     *
     * @return The decoded array of bytes. May be of length 0.
     *
     */
    public final static byte[] decodeFast(String s) {

        // Check special case

        int sLen = s.length();

        if (sLen == 0) {
            return new byte[0];
        }



        int sIx = 0, eIx = sLen - 1; // Start and end index after trimming.



        // Trim illegal chars from start

        while (sIx < eIx && IA[s.charAt(sIx) & 0xff] < 0) {
            sIx++;
        }



        // Trim illegal chars from end

        while (eIx > 0 && IA[s.charAt(eIx) & 0xff] < 0) {
            eIx--;
        }



        // get the padding count (=) (0, 1 or 2)

        int pad = s.charAt(eIx) == '=' ? (s.charAt(eIx - 1) == '=' ? 2 : 1) : 0; // Count

        // '='

        // at

        // end.

        int cCnt = eIx - sIx + 1; // Content count including possible

        // separators

        int sepCnt = sLen > 76 ? (s.charAt(76)
                == '\r'
                ? cCnt / 78 : 0) << 1
                : 0;



        int len = ((cCnt - sepCnt) * 6 >> 3) - pad; // The number of decoded

        // bytes

        byte[] dArr = new byte[len]; // Preallocate byte[] of exact length



        // Decode all but the last 0 - 2 bytes.

        int d = 0;

        for (int cc = 0, eLen = (len / 3) * 3; d < eLen;) {

            // Assemble three bytes into an int from four "valid" characters.

            int i = IA[s.charAt(sIx++)] << 18 | IA[s.charAt(sIx++)] << 12
                    | IA[s.charAt(sIx++)] << 6 | IA[s.charAt(sIx++)];



            // Add the bytes

            dArr[d++] = (byte) (i >> 16);

            dArr[d++] = (byte) (i >> 8);

            dArr[d++] = (byte) i;



            // If line separator, jump over it.

            if (sepCnt > 0 && ++cc == 19) {

                sIx += 2;

                cc = 0;

            }

        }



        if (d < len) {

            // Decode last 1-3 bytes (incl '=') into 1-3 bytes

            int i = 0;

            for (int j = 0; sIx <= eIx - pad; j++) {
                i |= IA[s.charAt(sIx++)] << (18 - j * 6);
            }



            for (int r = 16; d < len; r -= 8) {
                dArr[d++] = (byte) (i >> r);
            }

        }



        return dArr;

    }

    public static void main(String[] args) {

        System.out.println(Base64.encodeToString("5CC9D9B48EFCF2FDB766BFB00E08EEDF".getBytes()));

    }
}
